GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

GHSA-68F3-CX9X-C5JF

Vulnerability from github – Published: 2026-04-03 18:31 – Updated: 2026-07-14 15:31
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

net/sched: teql: Fix double-free in teql_master_xmit

Whenever a TEQL devices has a lockless Qdisc as root, qdisc_reset should be called using the seq_lock to avoid racing with the datapath. Failure to do so may cause crashes like the following:

[ 238.028993][ T318] BUG: KASAN: double-free in skb_release_data (net/core/skbuff.c:1139) [ 238.029328][ T318] Free of addr ffff88810c67ec00 by task poc_teql_uaf_ke/318 [ 238.029749][ T318] [ 238.029900][ T318] CPU: 3 UID: 0 PID: 318 Comm: poc_teql_ke Not tainted 7.0.0-rc3-00149-ge5b31d988a41 #704 PREEMPT(full) [ 238.029906][ T318] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 238.029910][ T318] Call Trace: [ 238.029913][ T318] [ 238.029916][ T318] dump_stack_lvl (lib/dump_stack.c:122) [ 238.029928][ T318] print_report (mm/kasan/report.c:379 mm/kasan/report.c:482) [ 238.029940][ T318] ? skb_release_data (net/core/skbuff.c:1139) [ 238.029944][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) ... [ 238.029957][ T318] ? skb_release_data (net/core/skbuff.c:1139) [ 238.029969][ T318] kasan_report_invalid_free (mm/kasan/report.c:221 mm/kasan/report.c:563) [ 238.029979][ T318] ? skb_release_data (net/core/skbuff.c:1139) [ 238.029989][ T318] check_slab_allocation (mm/kasan/common.c:231) [ 238.029995][ T318] kmem_cache_free (mm/slub.c:2637 (discriminator 1) mm/slub.c:6168 (discriminator 1) mm/slub.c:6298 (discriminator 1)) [ 238.030004][ T318] skb_release_data (net/core/skbuff.c:1139) ... [ 238.030025][ T318] sk_skb_reason_drop (net/core/skbuff.c:1256) [ 238.030032][ T318] pfifo_fast_reset (./include/linux/ptr_ring.h:171 ./include/linux/ptr_ring.h:309 ./include/linux/skb_array.h:98 net/sched/sch_generic.c:827) [ 238.030039][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) ... [ 238.030054][ T318] qdisc_reset (net/sched/sch_generic.c:1034) [ 238.030062][ T318] teql_destroy (./include/linux/spinlock.h:395 net/sched/sch_teql.c:157) [ 238.030071][ T318] __qdisc_destroy (./include/net/pkt_sched.h:328 net/sched/sch_generic.c:1077) [ 238.030077][ T318] qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159) [ 238.030089][ T318] ? __pfx_qdisc_graft (net/sched/sch_api.c:1091) [ 238.030095][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 238.030102][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 238.030106][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 238.030114][ T318] tc_get_qdisc (net/sched/sch_api.c:1529 net/sched/sch_api.c:1556) ... [ 238.072958][ T318] Allocated by task 303 on cpu 5 at 238.026275s: [ 238.073392][ T318] kasan_save_stack (mm/kasan/common.c:58) [ 238.073884][ T318] kasan_save_track (mm/kasan/common.c:64 (discriminator 5) mm/kasan/common.c:79 (discriminator 5)) [ 238.074230][ T318] __kasan_slab_alloc (mm/kasan/common.c:369) [ 238.074578][ T318] kmem_cache_alloc_node_noprof (./include/linux/kasan.h:253 mm/slub.c:4542 mm/slub.c:4869 mm/slub.c:4921) [ 238.076091][ T318] kmalloc_reserve (net/core/skbuff.c:616 (discriminator 107)) [ 238.076450][ T318] __alloc_skb (net/core/skbuff.c:713) [ 238.076834][ T318] alloc_skb_with_frags (./include/linux/skbuff.h:1383 net/core/skbuff.c:6763) [ 238.077178][ T318] sock_alloc_send_pskb (net/core/sock.c:2997) [ 238.077520][ T318] packet_sendmsg (net/packet/af_packet.c:2926 net/packet/af_packet.c:3019 net/packet/af_packet.c:3108) [ 238.081469][ T318] [ 238.081870][ T318] Freed by task 299 on cpu 1 at 238.028496s: [ 238.082761][ T318] kasan_save_stack (mm/kasan/common.c:58) [ 238.083481][ T318] kasan_save_track (mm/kasan/common.c:64 (discriminator 5) mm/kasan/common.c:79 (discriminator 5)) [ 238.085348][ T318] kasan_save_free_info (mm/kasan/generic.c:587 (discriminator 1)) [ 238.085900][ T318] __kasan_slab_free (mm/ ---truncated---

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-23449"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-415"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-03T16:16:31Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: teql: Fix double-free in teql_master_xmit\n\nWhenever a TEQL devices has a lockless Qdisc as root, qdisc_reset should\nbe called using the seq_lock to avoid racing with the datapath. Failure\nto do so may cause crashes like the following:\n\n[  238.028993][  T318] BUG: KASAN: double-free in skb_release_data (net/core/skbuff.c:1139)\n[  238.029328][  T318] Free of addr ffff88810c67ec00 by task poc_teql_uaf_ke/318\n[  238.029749][  T318]\n[  238.029900][  T318] CPU: 3 UID: 0 PID: 318 Comm: poc_teql_ke Not tainted 7.0.0-rc3-00149-ge5b31d988a41 #704 PREEMPT(full)\n[  238.029906][  T318] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n[  238.029910][  T318] Call Trace:\n[  238.029913][  T318]  \u003cTASK\u003e\n[  238.029916][  T318]  dump_stack_lvl (lib/dump_stack.c:122)\n[  238.029928][  T318]  print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)\n[  238.029940][  T318]  ? skb_release_data (net/core/skbuff.c:1139)\n[  238.029944][  T318]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)\n...\n[  238.029957][  T318]  ? skb_release_data (net/core/skbuff.c:1139)\n[  238.029969][  T318]  kasan_report_invalid_free (mm/kasan/report.c:221 mm/kasan/report.c:563)\n[  238.029979][  T318]  ? skb_release_data (net/core/skbuff.c:1139)\n[  238.029989][  T318]  check_slab_allocation (mm/kasan/common.c:231)\n[  238.029995][  T318]  kmem_cache_free (mm/slub.c:2637 (discriminator 1) mm/slub.c:6168 (discriminator 1) mm/slub.c:6298 (discriminator 1))\n[  238.030004][  T318]  skb_release_data (net/core/skbuff.c:1139)\n...\n[  238.030025][  T318]  sk_skb_reason_drop (net/core/skbuff.c:1256)\n[  238.030032][  T318]  pfifo_fast_reset (./include/linux/ptr_ring.h:171 ./include/linux/ptr_ring.h:309 ./include/linux/skb_array.h:98 net/sched/sch_generic.c:827)\n[  238.030039][  T318]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)\n...\n[  238.030054][  T318]  qdisc_reset (net/sched/sch_generic.c:1034)\n[  238.030062][  T318]  teql_destroy (./include/linux/spinlock.h:395 net/sched/sch_teql.c:157)\n[  238.030071][  T318]  __qdisc_destroy (./include/net/pkt_sched.h:328 net/sched/sch_generic.c:1077)\n[  238.030077][  T318]  qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159)\n[  238.030089][  T318]  ? __pfx_qdisc_graft (net/sched/sch_api.c:1091)\n[  238.030095][  T318]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)\n[  238.030102][  T318]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)\n[  238.030106][  T318]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)\n[  238.030114][  T318]  tc_get_qdisc (net/sched/sch_api.c:1529 net/sched/sch_api.c:1556)\n...\n[  238.072958][  T318] Allocated by task 303 on cpu 5 at 238.026275s:\n[  238.073392][  T318]  kasan_save_stack (mm/kasan/common.c:58)\n[  238.073884][  T318]  kasan_save_track (mm/kasan/common.c:64 (discriminator 5) mm/kasan/common.c:79 (discriminator 5))\n[  238.074230][  T318]  __kasan_slab_alloc (mm/kasan/common.c:369)\n[  238.074578][  T318]  kmem_cache_alloc_node_noprof (./include/linux/kasan.h:253 mm/slub.c:4542 mm/slub.c:4869 mm/slub.c:4921)\n[  238.076091][  T318]  kmalloc_reserve (net/core/skbuff.c:616 (discriminator 107))\n[  238.076450][  T318]  __alloc_skb (net/core/skbuff.c:713)\n[  238.076834][  T318]  alloc_skb_with_frags (./include/linux/skbuff.h:1383 net/core/skbuff.c:6763)\n[  238.077178][  T318]  sock_alloc_send_pskb (net/core/sock.c:2997)\n[  238.077520][  T318]  packet_sendmsg (net/packet/af_packet.c:2926 net/packet/af_packet.c:3019 net/packet/af_packet.c:3108)\n[  238.081469][  T318]\n[  238.081870][  T318] Freed by task 299 on cpu 1 at 238.028496s:\n[  238.082761][  T318]  kasan_save_stack (mm/kasan/common.c:58)\n[  238.083481][  T318]  kasan_save_track (mm/kasan/common.c:64 (discriminator 5) mm/kasan/common.c:79 (discriminator 5))\n[  238.085348][  T318]  kasan_save_free_info (mm/kasan/generic.c:587 (discriminator 1))\n[  238.085900][  T318]  __kasan_slab_free (mm/\n---truncated---",
  "id": "GHSA-68f3-cx9x-c5jf",
  "modified": "2026-07-14T15:31:45Z",
  "published": "2026-04-03T18:31:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23449"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/21c89a0a8de7eadad8d385645a95b3233f23130e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4a233447b941db451ea5f5a0942cffd0f7f7eaae"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4e8ebc4c18ea8213d28e6cb867d18fcc67daca21"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/66360460cab63c248ca5b1070a01c0c29133b960"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/afbc79a7770b230a9f24bd39271209d6b3682c5f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e9c66d3e7d8557b3308e55c613aa07254fe97611"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


Loading…